A variety of devices and systems have been used for locking or fastening sashes on windows and doors. See, for example, U.S. Pat. Nos. 47,537; 184,501; 532,935; 1,992,531; 2,018,346; 2,076,897; 2,098,249; 2,357,608; 2,845,789; and 3,082,617. Although some of such fastening systems involve the use of a movable bolt for preventing relative movement of one frame member relative to another frame member, such fastening systems exhibit a number of disadvantages and have not been entirely satisfactory.
Additional fastening systems are described, for example, in U.S. Pat. Nos. 8,286; 357,116; 876,429; 972,769; 985,652; 1,352,624; 1,509,619; 2,657,086; 2,477,524; and 3,233,932. These patents describe fastening systems involving movable bolts, some of which can be locked in a retracted position. However, the fastening systems described therein are cumbersome in use or require specialized hardware.
There has not heretofore been provided a locking method having the advantages and exhibiting the ease of use which are associated with the locking method of this invention.